.header{
    width: 100%;
    height: 50px;
    line-height: 50px;
}
.header :nth-child(1){
    font-size: 20px;
}
.header :nth-child(2){
    font-weight: bold;
    margin-left: 150px;
    font-size: 20px;
    text-align: center;
}